36 citations · 223 across the 12 of their papers we have counts for
12 papers
Grassmannian learning mutual subspace method for image set recognition
Lincon S. Souza, Naoya Sogi, Bernardo B. Gatto +2
This paper addresses the problem of object recognition given a set of images as input (e.g., multiple camera sources and video frames). Convolutional neural network (CNN)-based fra…
Demonstration of the nearly continuous operation of an Yb optical lattice clock for half a year
Takumi Kobayashi, Daisuke Akamatsu, Kazumoto Hosaka +6
Optical lattice clocks surpass primary Cs microwave clocks in frequency stability and accuracy, and are promising candidates for a redefinition of the second in the International S…
Improved Frequency Ratio Measurement with 87Sr and 171Yb Optical Lattice Clocks at NMIJ
Yusuke Hisai, Daisuke Akamatsu, Takumi Kobayashi +4
We report improved frequency ratio measurement with Sr and Yb optical lattice clocks at the National Metrology Institute of Japan (NMIJ). The Sr optical latti…
Potential for improving the local realization of coordinated universal time with a convolutional neural network
Takehiko Tanabe, Jiaxing Ye, Tomonari Suzuyama +3
The time difference between coordinated universal time (UTC) and a hydrogen maser, which is a master oscillator for the local realization of UTC at the National Metrology Institute…
Discriminant analysis based on projection onto generalized difference subspace
Kazuhiro Fukui, Naoya Sogi, Takumi Kobayashi +2
This paper discusses a new type of discriminant analysis based on the orthogonal projection of data onto a generalized difference subspace (GDS). In our previous work, we have demo…
Uncertainty evaluation of an Yb optical lattice clock at NMIJ
Takumi Kobayashi, Daisuke Akamatsu, Yusuke Hisai +6
We report an uncertainty evaluation of an Yb optical lattice clock with a total fractional uncertainty of , which is mainly limited by the lattice-induce…
Dual-Mode Operation of an Optical Lattice Clock Using Strontium and Ytterbium Atoms
Daisuke Akamatsu, Takumi Kobayashi, Yusuke Hisai +4
We have developed an optical lattice clock that can operate in dual modes: a strontium (Sr) clock mode and an ytterbium (Yb) clock mode. Dual-mode operation of the Sr-Yb optical la…
A frequency-stabilized light source at 399 nm using an Yb hollow-cathode lamp
Takehiko Tanabe, Daisuke Akamatsu, Hajime Inaba +5
We demonstrate a diode laser system operating at 399 nm that is stabilized to the electric dipole transition in ytterbium (Yb) atoms in…
Second harmonic generation at 399 nm resonant on the transition of ytterbium using a periodically poled LiNbO waveguide
Takumi Kobayashi, Daisuke Akamatsu, Yoshiki Nishida +4
We demonstrate a compact and robust method for generating a 399-nm light resonant on the transition in ytterbium using a single-pass periodically poled LiNbO$…
Absolute frequency measurements and hyperfine structures of the molecular iodine transitions at 578 nm
Takumi Kobayashi, Daisuke Akamatsu, Kazumoto Hosaka +6
We report absolute frequency measurements of 81 hyperfine components of the rovibrational transitions of molecular iodine at 578 nm using the second harmonic generation of an 1156-…
Improved frequency measurement of the - clock transition in Sr using the Cs fountain clock at NMIJ as a transfer oscillator
Takehiko Tanabe, Daisuke Akamatsu, Takumi Kobayashi +10
We performed an absolute frequency measurement of the - transition in Sr with a fractional uncertainty of , which is less than one thi…
A compact iodine-laser operating at 531 nm with stability at the 10 level and using a coin-sized laser module
Takumi Kobayashi, Daisuke Akamatsu, Kazumoto Hosaka +6
We demonstrate a compact iodine-stabilized laser operating at 531 nm using a coin-sized light source consisting of a 1062-nm distributed-feedback diode laser and a frequency-doubli…